This is a set of two ceramic shelves (170 mm (7.4/5″) wide x 125 mm (5″) x 6 mm (1/4″) thickness) with four muffle stands for these two shelves. You can use this set inside of chamber of R14-L and R14-LP kilns. Dimensions of muffle stands: 115 x 50 x 20 mm. No asbestos. Commercial graded product.